This invention relates, in general, to a method for removing unwanted material from surfaces, and more particularly to a method of removing unwanted material from workpiece surfaces employing a gaseous plasma comprising a reactive halogen species. A related invention is disclosed by the same inventors in U.S. Patent Application Ser. No. 07/327,630, filed Mar. 23, 1989, entitled "Nitride Removal Method", now U.S. Pat. No. 4,877,482.
Various surfaces are commonly coated for decoration, protection, to improve wear characteristics and to better interact with materials that they come into contact with. However, once many coatings begin to wear , it is extremely difficult to remove the remaining coating so that the surface may be recoated. Commonly used methods of removing coatings are reverse plating, wet chemical etches and media blast removal. These methods are often detrimental in that they will not uniformly remove coatings and may also damage the underlying surface. Damage to the underlying surface will often result in a need for rework or in extreme cases where critical dimensions must be maintained, render the surface non-usable.
Various coatings exist in the art today that are not used to their fullest extent due to the absence of a method to uniformly removing coatings once they begin to wear. An example is titanium nitride. In addition to the favorable characteristics mentioned above, titanium nitride has excellent lubricity and works well in conjunction with plastics. It would be highly beneficial to employ coatings such as titanium nitride in numerous endeavors if a method were available to remove it without damaging the underlying surface.